Question of the Day

Do you support a path to citizenship for Dreamers?

Accident investigators said yesterday that damaged thermal panels led to the fiery disintegration of Space Shuttle Columbia.The independent Columbia Accident Investigation Board presented the most complete picture yet to explain why the shuttle broke apart Feb. 1. But they aren’t prepared to attribute the breakup to a 2-pound chunk of foam insulation that peeled off the shuttle’s external fuel tank during liftoff and struck its left wing.The 13-member investigation board outlined a “working scenario” that lists 30 conclusions about Columbia’s Jan. 16 launch, orbit and fiery descent over central Texas. They released the preliminary conclusions after reaching consensus with the National Aeronautics and Space Administration’s own investigative team on facts about the inquiry and factors that led to the breakup that killed seven astronauts.”I would say we have a high level of agreement that this working scenario is something everyone can live with,” Harold W. Gehman Jr., the retired Navy admiral heading the independent inquiry, said during a press conference in Houston.The working hypothesis will help accident investigators draft a list of recommendations, which it expects to complete this summer. In its recommendations, investigators will try to pinpoint the direct cause of the Columbia breakup and contributing factors.The independent board and NASA’s team of investigators said they believe several pieces of foam insulation came off the fuel tank.Gregory Byrne, assistant manager of human exploration science at the Johnson Space Center, told investigators yesterday that film and photographs from two cameras show at least three pieces of foam peeling from Columbia’s fuel tank 81 seconds after liftoff.Investigators said one of those pieces hit the leading edge of the left wing, and Adm. Gehman said a breach probably formed on the lower portion of panel 8 or 9 or on the seal between the two pieces. It’s not clear just how big the hole was, but it could have been about 90 square inches.NASA and independent investigators also agreed that Columbia began its descent with a hole in the left wing.Upon re-entry, it took five minutes before sensors began recording rising temperatures and another three minutes for searing gases to penetrate that hole, Adm. Gehman said. Once flames pierced the left wing, it took just 90 seconds for thermal protection tiles to begin popping off the wing.Fragments of carbon panels from the leading edge of the left wing show extensive heat damage and are coated with slag from a number of metals, indicating the presence of extreme heat. Once the flame was inside, it quickly destroyed sensors throughout the wing’s interior. Information from the sensors stored on the shuttle’s data recorder has helped investigators piece together Columbia’s final moments.The shuttle continued to fly without problems, but irreversible massive damage was occurring.Investigators still must figure out whether the hole in the left wing that let in the scorchinggases was caused by foam insulation that shed from the fuel tank. Adm. Gehman held out the possibility yesterday that they may never be able to pin the cause on the foam.Micrometeorites or orbital junk also could have caused the breach.Even while they hesitated to lay the blame for the breach on foam insulation, investigators confirmed yesterday another instance of foam peeling from an external tank and hitting a shuttle. There are now six confirmed instances of foam hitting a shuttle, Air Force Maj. Gen. Kenneth W. Hess said.The working scenario still can change if new evidence surfaces.”We still have our antennas out for any indication that we’re wrong,” Adm. Gehman said.Even if investigators can’t say definitively that a strike from foam insulation started the chain of events leading to the shuttle’s destruction, they believe NASA can safely resume flying its grounded shuttle fleet.”We believe we have a good chance of coming up with recommendations that make the shuttle safe to fly,” Adm. Gehman said. “I’m not the least bit concerned.”But they can never make the shuttle program risk-free, Gen. Hess said.

The Washington Times Comment Policy

The Washington Times is switching its third-party commenting system from Disqus to Spot.IM. You will need to either create an account with Spot.im or if you wish to use your Disqus account look under the Conversation for the link "Have a Disqus Account?". Please read our Comment Policy before commenting.